Drill



May 23, 1939.

w. J. BAUROTH DRILL Original Filed April 14, 1936 2 Sheets-Sheet l H 22 W m wi w W Y B H 1} fi g y 1939- w. J. BAUROTH 2,159,671

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Original Filed April 14, 1936 2 Sheets-Sheet 2 f/VVf/VTOQ, WALTEIZ J. BAu oTH.

Patented May 23, 1939 UNITED STATES PATENT OFFICE DRILL ration of Ohio Application April 14, 1936, Serial No. 74,311 Renewed May 13, 1938 26 Claims.

This invention relates to a hand operated drill particularly of the type constructed for use in a coal mine.

An object of the invention is to provide an improved drill of the above mentioned type in which control means is provided for the motor thereof and which is biased to an open position and in which a control lever is provided on one handle of the drill to be operated by a finger of the opera- 1o tor without releasing his grip and without requiring any rotary or sliding movement of a supporting handle of the drill.

Another object of the invention is to provide an improved trigger switch control means for a hand operated drill.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. l is a front elevational view of the drill of my invention with one handle cut short, and with the cover for the switch housing removed;

Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1 looking in the direction of the arrows and showing my improved trigger switch operating mechanism;

Fig. 3 is a sectional elevational view of the control switch taken on the line 3-3 of Fig. 1 looking in the direction of the arrows;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2 looking in the direction of the arrows;

Figs. 5 and 6 are end views taken on the line 55 of Fig. 2 looking in the direction of the arrows; and

Fig. '7 is a plan view of the drill comprising my invention.

The invention herein disclosed comprises an improvement on the invention entitled Drilling machines, disclosed and claimed in the application of R. K. Jeffrey, Serial No. 725,504, filed May 14, 1934, and in the divisional application of R. K. Jeffrey for a Drilling machine switch, Serial No. 59,421, filed January 16, 1936.

Said application Serial No. 725,504 discloses and claims a drilling machine including specific means for cooling the motor, or the motor and control switch, while providing a gas tight casing, and a particular combination of elements which 5 provides a novel support forthe drill.

Said application Serial No. 59,421 discloses and claims a particular electric control switch and operating means therefor in which a handle is rotated to operate the switch, the handle being spring biased to a normal switch opening position, the specific structure of the switch being similar to that herein disclosed.

Referring particularly to Figs. 1, 2 and 7 of the drawings, it is to be seen that the drill comprises a motor casing or housing Ill within which is housed the electric motor for driving the drill bit or auger ll thereof. As is described in full detail in the above mentioned parent application of R. K. J efirey, appropriate reduction gearing is provided by the motor carried in housing 10 and the drill bit or augur socket 12 of said drill. To enhance the cooling of the motor, the casing 10 is also provided with a corrugated exterior surface. Extending radially from the casing l0, and in alignment, are a pair of rigid handles 13 and I! provided with appropriate gripping surfaces.

Forming a part of the motor casing or housing II! is a switch compartment l5 within which is housed a snap action type of switch which is disclosed in full detail and claimed in the above mentioned divisional application of R. K. J efirey. The structure of this switch will also be described more in detail hereinafter.

Referring particularly to Figs. 1 and 2, attention is directed to the operating mechanism for the switch I6 in compartment 15, which operating mechanism is so constructed that unless an affirmative act is performed the switch 16 will move to an open circuit position to stop the operation of the drill motor. As a consequence, should the drill be dropped it will automatically stop its operation. The particular operating mechanism also provides a completely inclosed construction except for a trigger lever which is to be engaged by a finger of the operator and provides a drill in which the supporting handles 13 and M are rigidly attached to the motor casing, thereby to provide the surest support for said drill at all times.

Extending laterally from the switch compartment I5 is an integral sleeve [1 adapted to receive a cooperating sleeve I8 forming a portion of the handle M. A spacer cylindrical bushing 19 is positioned between the sleeves l1 and E8, and ex- 1 tends into the switch compartment 15 a. slight distance. Sleeves l1 and I8 and bushing H! are rigidly held together by a machine screw 20. Extending through the sleeve I8 is a shaft 2| having at one end a bushing 22 provided with a pair of abutments 23 and 24. (See Figs. 5 and 6.)

The opposite end of the shaft 2| has a reduced neck 25 which receives the hub of a beveled gear 26 to which is rigidly attached a bushing 21. Bushings 22 and 21 mount the shaft for rotation in the sleeve I8 while preventing axial movement thereof. A screw 28 is threaded into the neck 25 to retain beveled gear 26 thereon and a pin 29 cooperates with an appropriate groove in gear 213 to insure its rotation with the shaft 21.

The gear 26 extends into a gear compartment 36 formed in the handle l lhaving a removable cover and bearing plate 3i. Mounted in said bearing plate 3| and extending through the gear compartment St on an axis perpendicular to the axis of shaft 29, is a stub shaft 32 to which is rigidly attached a beveled gear 33 meshing with the beveled gear 25. It is to be noted that gear 33 is larger than gear 25, and thus there will be a reduction from shaft 32 to shaft 2|. A pin (it is provided to attach stub shaft 32 and bevel gear The stub shaft 32 extends outwardly through a wall of gear compartment 36 and has attached to its outwardly extending portion a finger operated trigger lever 35 by means of a pin 36. The trigger lever 35 is in position to be readily grasped by the forefinger of an operator without removing his grip upon the handle M. This provides for a very ready operation of said trigger lever 35 by the operator while affording full opportunity to support the drill.

Cooperating with the trigger lever 55, is a stub abutment 3? carried by the handle M to restrict the movement of said trigger lever 35 in one direction. To bias the shaft ii to a normal switch opening position in which the trigger lever 35 will be held adjacent the abutment 3?, I provide a coil spring 38 formed in two sections and surrounding the shaft 25 while being within the sleeve 53. The central portion of the coil spring 38 is attached to the sleeve it by a rivet 39 while the two free ends thereof are attached to the shaft 2! by rivets it. As seen in Fig. 4 of the drawings, the coil spring 38 will tend to rotate the shaft 2! in a clockwise direction which will urge the trigger lever 55 against the abutment 3'1.

Referring particularly to the structure of the snap switch, as best seen in Figs. 1 and 3, it will be noted that said switch comprises a base member ll of insulating material which is mounted upon studs within the switch compartment [5. Spaced from said base member ti is a front plate also of insulating material. Said base member ii and said front plate at are spaced apart by insulating tubes i i and insulating block 45 formed integral with the base member M. Appropriate screws 45 extend through the tubes 44 and block (15 and thread into the studs 5-2 to hold the base member it and front plate 33 in position.

The base member il carries a stationary metallic contact ii which forms one electrode of the switch. Cooperating with said stationary contact 47 is a movable contact it mounted upon a leaf spring it carried upon a movable insulating block 53 which is pivoted to insulate block 15 about a pin 5!. Connection of the leaf spring d9 to the block is effected through a pin 52 provided with a coil spring 53 and an appropriate washer to urge the spring leaf 49 against the block 5 3. This insures a wiping connection between the movable contact 48 and the stationary contact 4?. Mounted upon the front of the plate i3 is a pair of fuse receiving clips 54 adapted to receive a fuse which may be connected in circuit with the motor.

spring leaves 49 are mounted upon a single block 5%. Between the two stationary contacts 4'! is provided a magnetic blow-out coil 56 adapted to aid in extinguishing any arc formed between either pair of switch contacts when the circuit is broken.

To swing the block 50 about the pin 5|, thereby to open or close the circuit to the motor, I provide a bail 57, one end of which is pivoted to a pin 53 (see Fig. l) in the switch compartment l5, and the other end of which is pivoted to a lug 59 ex tending into the switch compartment l5 and formed integral with the shaft 2|. (See Figs. 2., 5 and 6.) A coil spring 60 is attached at one end to the bail 51, and at the other end to a pin 55 carried by block 50. It will be evident that with the parts in the position shown in Fig. 3, the switch will be in open circuit position, and by swinging the bail 5'! about its pivots, the axis of the coil spring 6E] will pass across the axis of pin 5! and move the leaf springs 49 to a position to close the contacts 4'! and 48. A reverse movement of the bail 51 will cause contacts 41 and 48 to be broken. This particular construction provides for a snap action type of switch. However, to insure even more rapid opening of the contacts, a retaining spring latch 62 is mounted, as shown in Fig. 3, in position to cooperate with the bail 57 to hold the contacts. il and 48 in circuit closing position until a predetermined force is applied to the bail 51. When such a predetermined force is applied to said bail it will move very rapidly from its circuit closing position to its circuit opening position.

To provide an operative connection between the shaft 2i and the bail 5'1, and to provide such a connection which will insure a very rapid movement of said bail to open the circuit rapidly, there is wrapped around the lug 59 a coil spring 63. This coil spring 53 has one end 64 bent over to contact the bail 51. The other end of the coil spring63 contacts with abutment 24 of bushing 22. As a consequence, rotation of the shaft 21 in a counter-clockwise direction, as viewed in Figs. 5 and 6, will store energy in said coil spring 63, and will tend to cause the bail 51 to rotate in a counter-clockwise direction. A counter-clockwise direction of rotation of the bail 51, as seen in Figs. 5 and 6, will be seen as a clockwise direction of rotation in Fig. 3. Thus this rotation of shaft 2! will store energy in coil spring 83 which will tend to rotate the bail 51 in a clockwise direction, as viewed in Fig. 3. When suflicient energy is stored in said coil spring 63 to overcome the retaining action of latch 62 on bail 5i, said bail will be released by said latch 62 and moved very rapidly under the influence of coil spring 63 to a circuit opening position.

It may also be noted that the movement of the bail 51 is restricted by abutments 65 and 66 formed on the cylindrical bushing 19. It will be evident, of course, that Fig. 6 shows the closed circuit position of the bail 51 and Fig. 5 shows its open circuit position, which is realized when shaft 2i rotates in a counter-clockwise direction, as seen in Figs. 5 and 6, thus rotating the bushing 22 in said counter-clockwise direction.

It will thus be seen that unless the trigger lever 35 is operated, said trigger lever will assume the position illustrated in Fig. 1 under the influence of coil spring 38, and the bail 51 will assume the position illustrated in Fig. 3, thereby to open the contacts of the motor controlling switch. When the trigger lever 35 is operated by the finger of an operator and in a clockwise 75 direction, as viewed in Fig. 1, it will rotate the shaft 2| and therefore rotate the bushing 22 in a clockwise direction as viewed in Fig. 5. This rotation of the bushing 22 will cause the abutment 23 thereof to contact the bail 51 and rotate it about its pivots 58 and 59 sufficiently for the spring 60 to snap the switch |6 to its closed position. This same rotation of the shaft 2| will also tension the spring 36 for reverse or counterclockwise action of said shaft 2| upon release of the lever 35. As shown in Fig. 5, upon clockwise rotation of the abutments 23 and 24 the spring 63 will rotate in a like direction by virtue of the force received by end 64 in contact with the bail 51, with the opposite end in contact with abutment 24. The release of lever 35 will permit spring 38 to rotate the shaft 2| and the abutments 23 and 24 in a counter-clockwise direction as viewed in Figs. 5 and 6, but the action of latch 62 retards the movement of bail 51 until sufficient energy is built up in spring 63 to overcome said action. Upon release of the bail 51 by the latch 62, the energy of the spring 63 causes said bail to carry the axis of spring 6|] rapidly across the axis of pivot 5| whereupon said spring 6!) acts quickly to snap open the contacts 41 and 48 of switch l6.

The device of my invention provides for the supporting of the drill by both handles I3 and I4, both to hold the drill up and to prevent its rotation about the axis of said handles. The construction of the switch operating mechanism provides for ready operation of the control switch while the drill is thus supported, and for immediate and automatic opening of said control switch when the trigger lever 35 is released for any purpose. In addition, the complete operating mechanism for said control switch is entirely inclosed within the housing formed by the handle |4 except for the trigger lever 35.

It may also be noted that the cover and gearing plate 3| provides a bearing for the stub shaft 32, and at the same time provides access to the gear compartment 30 for the purpose of applying lubrication to said compartment, and for inspection or renewal of any of the parts contained therein, such as gears 26 and 33.

It may also be noted that the entire operating mechanism, including the handle |4, may be readily removed by the expedient of removing the machine screw 20 and rotating the handle |4 approximately thirty degrees to permit alignment between retaining bosses 61 on handle l4 and cooperating notches 68 on sleeve H, which notches provide access to a peripheral retaining groove in sleeve H which receives said bosses 61, as seen in Figs. 1 and 4.

It may also be noted that a removable cover plate 69 is provided for the switch compartment |5 to permit ready access thereto.

It will be understood that unless a contrary description is herein given, the structure of the drill will follow the disclosure of the above mentioned application of R. K. Jeffrey, Serial No. 725,504.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and I therefore wish not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

1. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing, handles extending laterally of said casing and rigidly attached thereto against rotary or sliding movement, switch means for controlling the motor, and control means for said switch comprising a finger operated lever on one handle, an operating shaft extending through said handle, spring means biasing said shaft to a position to open said switch, and means including a pair of reduction gears for connecting said lever and said shaft.

2. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing, handles extending laterally of said casing and rigidly attached thereto against rotary or sliding movement, switch means for controlling the motor, and control means for said switch comprising a finger operated lever on one handle, an operating shaft extending through said handle, spring means biasing said shaft to a position to open said switch, and means including a pair of gears for connecting said lever and said shaft.

3. A switch control mechanism for a drill comprising a handle, a shaft in said handle, spring means biasing said shaft to one position, a second shaft at right angles to said first shaft, beveled gears interconnecting said shafts, and a finger operated lever for controlling said second shaft.

4. A switch control mechanism for a drill comprising a handle, a shaft in said handle, spring means biasing said shaft to one position, a second shaft at right angles to said first shaft, gears I interconnecting said shafts, and a finger operated lever for controlling said second shaft.

5. A switch control mechanism for a drill comprising a handle, a shaft in said handle, spring means biasing said shaft to one position, a second shaft at right angles to said first shaft, reduction gears interconnecting said shafts, and a finger operated lever for controlling said second shaft.

6. A hand operated drill comprising a motor and a casing, a drill bit holder extendng from said casing and driven by said motor, aligned handles for supporting said drill, control means for said motor, a finger operated lever for operating said control means and positioned to be reached without the operator releasing his grip on said handles, and a shaft Within a handle for connecting said lever and said control means.

'7. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing and driven by said motor, aligned handles for supporting said drill, control means for said motor, a finger operated lever for operating said control means and positioned to be reached without the operator releasing his grip on said handles, a shaft operated by said lever, said shaft being connected to said control means through a flexible connecting member.

8. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing and driven by said motor, aligned handles for supporting said drill, control means for said motor, a finger operated lever for operating said control means and positioned to be reached without the operator releasing his grip on said handles, a shaft within a handle for connecting said lever and said control means, and means biasing said shaft to a position to stop said motor.

9. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing and driven by said motor, aligned handles for supporting said drill, control means for said motor, a finger operated lever for operating said control means and positioned to be reached without the operator releasing his grip on said handles, a shaft Within a handle for connecting said lever and said control means, and means biasing said shaft to a position to stop said motor, said means comprising a coil spring sur rounding said shaft.

10. A hand operated drill comprising a motor and a casing, a drill bit holder extending from said casing and driven by said motor, aligned handles for supporting said drill, control means for said motor, a finger operated lever for operating said control means and positioned to be reached Without the operator releasing his grip on said handles, a shaft within a handle for connecting said lever and said control means, and means biasing said shaft to a position to stop said motor, said means comprising a coil spring surrounding said shaft, and having its center attached to the shaft and its two ends attached to the handle.

11. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle, a shaft in said handle, a finger trigger, gears connecting said trigger and shaft, and energy storing spring means connecting said shaft and motor controlling means.

12. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a shaft, a trigger, gears connecting said shaft and trigger, and energy storing means connecting said shaft and motor controlling means.

13. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle, a shaft in said handle, an operating lever, gears connecting said lever and shaft, and spring means for biasing said shaft to a predetermined position.

14. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle, a shaft therein, a coil spring surrounding said shaft and connected thereto and to said handle, and means for operating said shaft to cause rotation thereof.

15. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for control1ing said motor, and operating means for said control means comprising a supporting handle forming a housing, a shaft within said housing mounted for rotation, a coil spring with-- in said handle housing and surrounding said shaft and being anchored at its center to said housing and at its ends to said shaft, and means for rotating said shaft.

16. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control'means comprising a supporting handle forming a gear casing, an operating shaft in said handle, an operating lever carried on a shaft extending into said gear casing, and intermeshing gears carried by said shafts.

17. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle forming a gear casing, an operating shaft in said handle parallel to the longitudinal axis thereof, a shaft extending into said gear casing at right angles to said first shaft, gears in said casing connecting said shafts, and an operating lever for said second named shaft.

18. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle forming a gear casing, an operating shaft in said handle, a shaft extending into said gear casing at right angles to said first shaft, gears in said casing connecting said shafts, and an operating lever for said second named shaft.

19. A hand operated drill comprising a motor and a casing, a drill socket extending from said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle forming a gear casing, an operating shaft in said handle parallel to the longitudinal axis thereof, a shaft extending into said gear casing at right angles to said first shaft, gears in said casing connecting said shafts, an operating lever for said second named shaft, and a cover for said casing providing a bearing for said second named shaft.

20. A hand operated drill comprising a motor and a casing, a drill socket extending from. said casing and driven by said motor, means for controlling said motor, and operating means for said control means comprising a supporting handle forming a gear casing, an operating shaft in said handle, a shaft extending into said gear casing at right angles to said first shaft, gears in said casing connecting said shaft, an operating lever for said second named shaft, and a cover for said casing providing a bearing for said second named shaft.

21. A hand operated drill comprising a motor and a casing, a control switch for said motor within said casing, a supporting handle, operating means for said switch within said handle and extending into said casing, said casing including a sleeve for telescopically receiving a cooperating sleeve on said handle, said sleeves being removably attached by a groove on one of said sleeves and a cooperating boss on the other.

22. A drilling machine comprising a casing, an electric motor within said casing, a drill socket connected to said motor for rotation thereby, an electric snap switch for controlling said motor, alined handles extending in opposite direction from said casing and adapted to be grasped by the operator, and mechanism comprising a pivoted lever associated with one of said handles for effecting movement of said snap switch to closed position when the operator grasps said last named handle and actuates said lever and for effecting automatic restoration of said snap switch to open position when said lever is released by the operator.

23. A drilling machine comprising an electric motor, an electric switch for controlling the same, a drill socket connected to said motor to be driven thereby, a casing enclosing said motor and said electric switch, gearing within said casing and connected to said switch to operate the same to closed position to start the motor, means operable from Without the casing to actuate said gearing to effect such closure of said switch, and a spring mounted within said casing and associated with said gearing to be wound up by the actuation of said gearing and adapted to effect the automatic opening of said switch when said actuating means is released.

24. A drilling machine comprising a casing, a motor therein, means comprising gearing within said casing and actuatable from without the casing for controlling said motor, said gearing comprising a shaft, and a removable cover having a bearing for one end of said shaft.

25. A drilling machine comprising a casing, a motor therein, a drill socket connected to said motor to be driven thereby, a handle connected to said casing by a bayonet joint, removable means for securing said handle to said casing in fixed relation thereto, and mechanism operable from without said handle and extending through one end thereof into said casing for controlling said motor.

26. A drilling machine comprising a casing, an electric motor therein, an electric snap switch comprising a spring mounted to hold said switch in either open position or closed position, a rock shaft, a direct actuating connection between said shaft and said switch to effect closure thereof when said shaft is rocked in one direction manually, a second spring connected to said shaft to be wound up thereby when said shaft is thus manually rocked, a third spring between said shaft and said switch and arranged to be automatically put under compression by said shaft when rocked in the opposite direction by said second spring when said shaft is released, a device in position to engage said switch to retard initial movement thereof toward open position to enable said third spring to assist the first spring to secure the opening of the switch with a snap action, and a drill socket connected to said electric motor for rotation thereby when said switch is closed by the manual rocking of said shaft, the rotation of said drill socket being automatically stopped when said rock shaft is automatically restored to its initial position.

WALTER J. BAUROTH. 

